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The Implantable cardioverter-defibrillator (ICD) has been proven to improve survival in adults with congenital heart disease (ACHD), however it is associated with a high rate of complications. We aimed to quantify the incidence of early (≤3 months) and late (3 months) complications (EC, LC) in ACHD patients implanted with an ICD and identify their clinical predictors.We retrospectively reviewed 207 patients who had ICD follow-up at Toronto General Hospital between 1996 and 2019.Most common diagnoses were Tetralogy of Fallot (32.4%), dextro-transposition of the great arteries (17.9%), congenital corrected transposition of the great arteries (13%). No intraprocedural complications were observed. Median follow up was 3.4 years (0.1-23). 24 patients (12%) developed EC (4 hematomas, 20 lead dislodgments). A total of 56 LC occurred (46% lead failure, 21% infection, 11% prophylactic lead extraction, 9% neurologic pain, 9% erosion, 4% other) with an incidence rate of LC of 18% per 5 person-years. Anatomic complexity (odds ratio 2.9,p=0.02) and CRTD implant(OR 2.5,p=0.04) were associated with EC. Survival free from LC was 92%, 86%, 65% respectively after 1,5 and 10 years. Presence of legacy leads (hazard ratio 2.9,p=0.006) and subpulmonary ejection fraction (5% increase, HR 1.35,p=0.031) were associated with LC.ACHD patients at risk of SCD continue to benefit from newer device technology. However, these patients-particularly those with greater anatomic and device complexity-remain at increased risk of developing complications over their lifetime. Given the life expectancy of this population, careful consideration needs to be given when a device for primary prevention is being contemplated.

BACKGROUND: Sudden cardiac death (SCD) is the main preventable cause of death in patients with adult congenital heart disease (ACHD). Since robust risk stratification methods are lacking, we developed a risk score model to predict SCD in patients with ACHD: the PRospEctiVE study on implaNTable cardIOverter defibrillator therapy and suddeN cardiac death in Adults with Congenital Heart Disease (PREVENTION-ACHD) risk score model. OBJECTIVE: The purpose of this study was to prospectively study predicted SCD risk using the PREVENTION-ACHD risk score model and actual SCD and sustained ventricular tachycardia/ventricular fibrillation (VT/VF) rates in patients with ACHD. METHODS: The PREVENTION-ACHD risk score model assigns 1 point each to coronary artery disease, New York Heart Association class II/III heart failure, supraventricular tachycardia, systemic ejection fraction < 40%, subpulmonary ejection fraction < 40%, QRS duration ≥ 120 ms, and QT dispersion ≥ 70 ms. SCD risk was calculated for each patient. An annual predicted risk of ≥3% constituted high risk. The primary outcome was SCD or VT/VF after 2 years. The secondary outcome was SCD. RESULTS: The study included 783 consecutive patients with ACHD (n=239 (31%) left-sided lesions; n=138 (18%) tetralogy of Fallot; n=108 (14%) closed atrial septal defect; median age 36 years; interquartile range 28-47 years; n=401 (51%) men). The PREVENTION-ACHD risk score model identified 58 high-risk patients. Eight patients (4 at high risk) experienced the primary outcome. The Kaplan-Meier estimates were 7% (95% confidence interval [CI] 0.1%-13.3%) in the high-risk group and 0.6% (95% CI 0.0%-1.1%) in the low-risk group (hazard ratio 12.5; 95% CI 3.1-50.9; P < .001). The risk score model's sensitivity was 0.5 and specificity 0.93, resulting in a C-statistic of 0.75 (95% CI 0.57-0.90). The hazard ratio for SCD was 12.4 (95% CI 1.8-88.1) (P = .01); the sensitivity and specificity were 0.5 and 0.92, and the C-statistic was 0.81 (95% CI 0.67-0.95). CONCLUSION: The PREVENTION-ACHD risk score model provides greater accuracy in SCD or VT/VF risk stratification as compared with current guideline indications and identifies patients with ACHD who may benefit from preventive implantable cardioverter-defibrillator implantation. ispartof: HEART RHYTHM vol:18 issue:5 pages:785-792 ispartof: location:United States status: published

Background: Implantable cardioverter defibrillators (ICDs) are effective in preventing arrhythmic sudden cardiac death in patients with tetralogy of Fallot (TOF). Although ICD therapies for malignant ventricular arrhythmias can be life-saving, shocks could have deleterious consequences. Substrate-based ablation therapy has become the standard of care to prevent recurrent ICD shocks in patients with ischemic cardiomyopathy. However, the efficacy and safety of this invasive therapy in the prevention of recurrent ICD shocks in patients with TOF has not been well evaluated. Methods: Records of a total of 47 consecutive TOF patients (mean age: 43.1 ± 13.2 years, male sex: n = 34 [72.3%]) who underwent ICD implantation for secondary prevention between 2000 and 2018 were reviewed. Results: Twenty (42.6%) patients underwent invasive therapy (radiofrequency catheter ablation, n = 8; surgical ablation with pulmonary valve replacement, n = 12) before ICD implantation. Twenty-seven patients (57.4%) were managed noninvasively. During follow-up (median 80.5 [interquartile range, 28.5-131.0] months), 2 (10.0%) patients in the invasive group and 10 (37.0%) patients in the noninvasive group received appropriate ICD shocks (P = 0.036). Logistic regression analysis showed that invasive therapy was associated with a decreased risk of ICD shocks by 81.1% (odds ratio, 0.189; 95% confidence interval, 0.036-0.990; P = 0.049). Furthermore, invasive therapy was associated with decreased risk of the composite outcomes of ICD shock, death, cardiac transplantation, and hospital admission (odds ratio, 0.090; 95% confidence interval, 0.025-0.365; P = 0.013) compared with noninvasive therapy. Conclusions: Invasive substrate modification therapy was associated with a lower likelihood of ICD shocks and improvement of long-term outcomes in TOF patients. Résumé: Contexte: Les défibrillateurs cardioverteurs implantables (DCI) sont efficaces pour prévenir la mort cardiaque subite provoquée par une arythmie chez les patients présentant une tétralogie de Fallot (TF). Bien que le traitement des arythmies ventriculaires malignes par DCI puisse sauver des vies, les chocs administrés peuvent avoir des conséquences délétères. L’ablation du substrat est devenue le traitement de référence pour prévenir l’administration à répétition de chocs par DCI chez les patients atteints d’une cardiomyopathie ischémique. L’efficacité et l’innocuité de ce traitement invasif pour prévenir l’administration de chocs répétés chez les patients présentant une TF n’ont toutefois pas été bien évaluées. Méthodologie: Nous avons examiné les cas consécutifs de 47 patients présentant une TF (âge moyen : 43,1 ± 13,2 ans; hommes : n = 34 [72,3 %]) ayant reçu un DCI en prévention secondaire entre 2000 et 2018. Résultats: Au total, 20 (42,6 %) patients ont subi un traitement invasif (ablation par cathéter par radiofréquence, n = 8; ablation chirurgicale et remplacement de la valve pulmonaire, n = 12) avant l’implantation d’un DCI. Vingt-sept patients (57,4 %) ont été pris en charge de façon non invasive. Au cours de la période de suivi (durée médiane de 80,5 [intervalle interquartile : 28,5 à 131,0] mois), 2 (10,0 %) patients du groupe ayant subi une intervention invasive et 10 (37,0 %) patients du groupe ayant subi une intervention non invasive ont reçu un choc approprié par DCI (p = 0,036). Les résultats de l’analyse par régression logistique montrent que le traitement invasif est associé à une réduction du risque de choc par DCI de 81,1 % (rapport des cotes : 0,189; intervalle de confiance à 95 % : de 0,036 à 0,990; p = 0,049). En outre, le traitement invasif est associé à une réduction du risque de survenue d’un des événements du paramètre d’évaluation composé, soit un choc administré par DCI, le décès, une transplantation cardiaque ou une hospitalisation (rapport des cotes : 0,090; intervalle de confiance à 95 % : de 0,025 à 0,365; p = 0,013) par rapport au traitement non invasif. Conclusions: La modification invasive du substrat a été associée à une probabilité plus faible de choc administré par DCI et à une amélioration des résultats à long terme chez les patients présentant une TF.

Early surgical tetralogy of Fallot (ToF) repair involved patching across the pulmonic annulus (transannular patch [TAP] repair), which resulted in severe pulmonic regurgitation. Long-term outcome improvements were anticipated with modifications that preserved the pulmonic annulus (annulus-preserving [AP] repair). The objective of the present study was to evaluate the need for late reintervention in adults with AP repair and those with TAP repair.We conducted a retrospective review of adults (born 1981-1996) with childhood intracardiac ToF repairs at a tertiary care center. The primary cardiovascular outcome was need for reintervention after primary intracardiac repair of ToF. Secondary outcomes included a composite of death, heart failure, and ventricular arrhythmias.Two hundred thirty adults were included: 104 with AP repair and 126 with TAP repair. The median age at last follow up was 25 years (interquartile range [IQR] 20-28) and the median follow-up duration was 7.9 years (IQR 3.5-12). Reintervention of any type was significantly more common in the TAP group during both childhood and adulthood (72.2% TAP vs 20.2% AP, HR 5.5, 95% CI 3.4-9.0; P0.001). Pulmonary valve replacement (PVR) was almost 6 times more likely in adults with TAP repair (65.1% TAP vs 16.3% AP, HR 5.7, 95% CI 3.4-9.7; P0.001).Patients who had AP ToF repair had significantly fewer late reinterventions compared with TAP repair, with the majority of reinterventions due to PVR. More long-term follow-up is required.

BackgroundPatients with Fontan circulation are known to be at high risk for developing atrial tachyarrhythmias (AAs). Our objective was to examine the efficacy and safety of amiodarone in the management of ATs in adult Fontan patients.MethodsPrimary outcomes of this single-centre, retrospective study included freedom from AAs and incidence of adverse effects of amiodarone on Fontan patients. Heart failure (HF) events and composite outcomes of death from any cause, Fontan revision and heart transplantation were evaluated as secondary outcomes. Predictors of HF and discontinuing amiodarone were also evaluated.ResultsA total of 61 patients (mean age 31.6±11.3 years, 40.9% female), who were treated with amiodarone in between 1995 and 2018, were included. AAs free survival at 1, 3 and 5 years were 76.2%, 56.9% and 30.6%, respectively. During a median follow-up of 50.5 months, 34 (55.7%) patients developed side effects, and 20 (32.8%) patients discontinued amiodarone due to side effects. Thyroid dysfunction was the most common side effect (n=26, 76.5%), amiodarone-induced thyrotoxicosis (AIT) (n=16, 27.1%) being most common thyroid dysfunction. Young age (age ConclusionsShort-term efficacy of amiodarone in Fontan physiology is acceptable. However, long-term administration is associated with a reduction of efficacy and a significant prevalence of non-cardiac side effects. AIT is associated with exacerbation of HF. The judicious use of amiodarone administration should be considered in this population.

While Floating Offshore Wind (FOW) represents a significant opportunity to foster wind energy development and to contribute to remarkable CO2 emissions reductions, its associated operational costs are still substantially above grid parity, and significant innovation is needed. MooringSense is a research and innovation project which explores digitisation technologies to enable the implementation of risk-based integrity management strategies for mooring systems in the FOW sector with the aim to optimise Operations and Maintenance (O&M) activities, reduce costs, and increase energy production. As part of this project, a risk-based assessment methodology specific for the mooring system of Floating Offshore Wind Turbines (FOWT) has been developed; this allows the development of a risk-based Mooring Integrity Management Strategy that can result in more cost-effective inspection planning. The methodology shall utilise the information made available by numerical tools, sensors, and algorithms developed in the project to update the risk level of the mooring system and set the required plan to mitigate the risk. Leveraging the additional information from monitoring technologies and predictive capabilities to determine the mooring system condition and remaining lifetime, the strategy provides the criteria for optimal decision making with regards to selection of O&M activities. The risk-based strategy developed allows for optimal planning of inspection and maintenance activities based on dynamic risk level that is periodically updated through the interface with the Digital Twin (DT). The validation of the strategy will demonstrate potential cost saving and economic advantages, however, it is expected that the overall MooringSense approach can reduce FOW farm operational costs by 10-15% and increase operational efficiency by means of an Annual Energy Production increase by 2-3%. The MooringSense project comprises of the development and validation of innovative solutions coming from multiple disciplines such as numerical modelling, simulation, Global Navigation Satellite System (GNSS), Structural Health Monitoring (SHM), and control systems which will provide valuable input to the risk-based mooring integrity management strategy.

Mapping and ablation of atrial tachycardia (AT) is commonly performed in lateral tunnel Fontan (LTF) patients, yet there is little information on the need of baffle puncture to access the pulmonary venous atrium (PVA). This study aimed to evaluate the most common chamber location of critical sites for majority of AT in LTF patients. Consecutive LTF patients underwent catheter-based high-density mapping and ablation of AT from Nov. 2015 to Mar. 2019. Critical sites were identified by a combination of activation and entrainment mapping. Acute procedural success was defined as AT termination with ablation and non-inducibility of any AT. Predictors for ablation failure were evaluated in retrospect. Fifteen catheter ablation procedures were performed in 9 patients. A total of 15 clinical ATs (mean TCL 369 ± 91 ms) were mapped. The mechanism was macro re-entry in 11 (73%) and micro re-entry in 2. In 11 ATs (73%), 94 ± 5% of tachycardia cycle length (TCL) were mapped inside the tunnel. The commonest site of successful ablation in the tunnel was on the lateral wall (60%). Trans-baffle access was obtained during 5 of 15 procedures (33%). Overall, procedural success was achieved in 9 of 15 procedures (60%). There were no complications. Recurrence of AT was 42% over a follow-up period of 4.3 ± 3.2 years. Faster TCL of 200–300 ms showed a trend towards ablation failure, (OR 17, 95% CI 0.7 to 423, p = 0.08). Catheter ablation can be performed effectively for ATs in LTF patients usually from inside the tunnel. ATs with critical sites in the PVA are uncommon. This information will help plan ablation in LTF patients without resorting to initial trans-baffle access.

A five-year-old, male entire Jack Russell terrier presented for a two-month history of ambulatory paraparesis lateralised to the left. Neurological examination localised to an L4–S3 myelopathy. MRI revealed an equivocal intramedullary lesion at the level of the L4–L5 disc space occupying 80 per cent of the spinal cord area. The mass was surgically resected. Histopathology confirmed the mass to be consistent with a meningioma in which a high proportion of neoplastic cells exhibited clear cytoplasm that stained positively with periodic acid-Schiff and was diastase-sensitive. This mass was assigned grade II/atypical (World Health Organization human system) based on the predominant clear cell morphology and a mitotic count of 10 mitotic figures in 10 high-power fields. To the authors’ knowledge, this is the first reported case of a clear cell meningioma in a dog.

Background Atrial tachyarrhythmias (AAs) are the main source of morbidity and mortality in adult congenital heart disease (ACHD). Direct-current cardioversion (DCCV) is an effective method to acutely terminate AAs, but many patients require repeated DCCV. Little is known about the impact of radiofrequency catheter ablation (RFCA) of AAs on the incidence of repeated DCCV in patients with ACHD. The purpose of this study was to evaluate the impact of RFCA on the incidence of DCCV in patients with ACHD. Methods A total of 157 patients with ACHD undergoing DCCV in our hospital from 2011 to 2018 (female n = 76 [48.4%], mean age 37.8 ± 12.5 y), were reviewed. The median follow-up period was 31.8 months (interquartile range 16.3-55.1 mo). Results Out of the total of 157 patients, 102 (65.0%) underwent RFCA for AAs, and 55 (35.0%) were treated without RFCA. Successful RFCA with termination of AAs during ablation was 62.7%. More than one-half of the patients had complex forms of CHD (62.4%). During follow-up, 57 patients (55.9%) who had RFCA developed recurrence of AAs, and 36 patients (35.2%) underwent repeated DCCV. Thirty-three (60.0%) out of 55 patients without RFCA required repeated cardioversion. Compared with patients without RFCA, RFCA significantly reduced the need for repeated DCCV by 40% (hazard ratio [HR] 0.60, 95% confidence interval [CI] 0.23-0.80; P = 0.009). In multivariate analysis, successful RFCA was associated with reduced risk of DCCV (HR 0.41, 95% CI 0.19-0.92; P = 0.031). Conclusions AAs remain common despite RFCA in patients with ACHD. Nevertheless, RFCA is associated with a marked reduction in the need for repeated DCCV.

This chapter presents and dissects the creation and exhibition of two recent works by the author; Visaurihelix, a site-specific, interactive, vertical 6.1 audiovisual installation commissioned for the Mackintosh tower at Glasgow’s design and architecture museum, The Lighthouse (July 2018-Jan 2019); and Alocas, a dual-screen, 4.1 audiovisual installation, most recently presented at the Stephen Lawrence Gallery, London, as part of the SOUND/IMAGE18 exhibition (Nov-Dec 2018). In both of the works presented and discussed, the architecture of the space in which they’re presented, alongside the positioning of the speakers and the interference patterns generated by the musical material present in the works, create constantly evolving, rhythmically shifting, and multi-directional audiovisual experiences which in turn shape and sculpt the audience’s perception of the sonic and visual materials in the work. This chapter considers the potential of developing work for Expanded Audiovisual Format (EAF), through examining how these two recent works engage with space and, crucially, site, in developing non-linear, algorithmic aleatoricism, and in considering experiential aspects as key defining elements in the development of audiovisual compositions for installation contexts.

Background Implantable cardioverter-defibrillators (ICDs) have been proven to prevent sudden cardiac death in adult congenital heart disease (ACHD) patients. Although the left side is chosen by default, implantation from the right side is often required. However, little is known about the efficacy and safety of right-sided ICDs in ACHD patients. Methods In this study we reviewed a total of 191 ACHD patients undergoing ICD/cardioverter resynchronisation therapy-defibrillator (CRT-D) implantation at our hospital between 2001 and 2019 (134 men and 57 women; age [mean ± standard deviation], 41.5 ± 14.8 years). Results Twenty-seven patients (14.1%) had right-sided devices. The most common causes of right-sided implantation were persistent left superior vena cava and vein occlusion (37.0%). Although procedure time (202.8 ± 60.5 minutes vs 143.8 ± 69.1 minutes, P = 0.008) was longer and the procedural success was lower (92.6% vs 99.4%, P = 0.008) for right-sided devices, no difference in R-wave and pacing threshold were noted. Among the 47 patients (24.6%) who underwent defibrillation threshold testing (DFT), no difference in DFT was observed (25.2 ± 5.3 J vs 23.8 ± 4.1 J, P = 0.460). During the median follow-up of 42.4 months, appropriate ICD therapy was observed in 5 (18.5%) and 30 (18.3%) patients for right- and left-sided ICDs/CRTDs, respectively (P = 0.978). No significant difference was seen in complications between them. Conclusions Implantation of an ICD on the right side is technically challenging, but it is feasible as an alternative approach for ACHD patients with contraindications to left-sided device implantation.

Aims In adults with congenital heart disease (CHD) heart failure is one of the leading causes of morbidity and mortality but experience with and reported outcome of cardiac resynchronization therapy (CRT) is limited. We investigated the efficacy of CRT in adults with CHD.Methods and results This was a retrospective study including 48 adults with CHD who received CRT since 2003 in four tertiary referral centres. Responders were defined as patients who showed improvement in NYHA functional class and/or systemic ventricular ejection fraction by at least one category. Ventricular function was assessed by echocardiography and graded on a four point ordinal scale. Median age at CRT was 47 years (range 18-74 years) and 77% was male. Cardiac diagnosis included tetralogy of Fallot in 29%, (congenitally corrected) transposition of great arteries in 23%, septal defects in 25%, left sided lesions in 21%, and Marfan syndrome in 2% of the patients. The median follow-up duration after CRT was 2.6 years (range 0.1-8.8). Overall, 37 out of 48 patients (77%) responded to CRT either by improvement of NYHA functional class and/or systemic ventricular function. There were 11 nonresponders to CRT. Of these, three patients died and four underwent heart transplantation.Conclusion In this cohort of older CHD patients, CRT was accomplished with a success rate comparable to those with acquired heart disease despite the complex anatomy and technical challenges frequently encountered in this population. Further studies are needed to establish appropriate guidelines for patient selection and long term outcome.

The risk of ventricular arrhythmias in the adult congenital heart disease population increases with age. The mechanism, type, and frequency vary depending on the complexity of the defect, whether it has been repaired, and the type and timing of repair. Risk stratification for sudden death in patients with congenital heart disease is often challenging. Current recommendations provide a useful guide for management of these patients and risk stratification continues to evolve. Internal cardiac defibrillator implantation is often challenging due to limited transvenous access, often resulting in the need for epicardial or subcutaneous devices.

OBJECTIVE: Adult congenital heart disease (ACHD) patients are at risk of sudden cardiac death (SCD). However, methods for risk stratification are not yet well-defined. The Tpeak -Tend (TpTe) interval, a measure of dispersion of ventricular repolarization, is a risk factor for SCD in non-ACHD patients. We aim to evaluate whether TpTe can be used in risk stratification for SCD in ACHD patients. DESIGN: From an international multicenter cohort of 25 790 ACHD patients, we identified all SCD cases. Cases were matched to controls by age, gender, congenital defect, and (surgical) intervention. OUTCOME MEASURES: TpTe was measured on a standard 12-lead ECG. The maximum TpTe of all ECG leads (TpTe-max), mean (TpTe-mean), and TpTe dispersion (maximum minus minimum) were obtained. Odds ratios (OR) for SCD cases vs controls were calculated using conditional logistic regression analysis. RESULTS: ECGs were available for 147 cases (median age at death 33.5 years (quartiles 26.2, 48.7), 66% male) and 267 controls. The mean TpTe-max was 97 ± 24 ms in cases vs 84 ± 17 ms in controls (P

Background Many adult congenital heart disease (ACHD) patients are at risk of sudden cardiac death (SCD). An implantable cardioverter-defibrillator (ICD) may prevent SCD, but the evidence for primary prevention indications is still unsatisfactory. Study Design PREVENTION-ACHD is a prospective study with which we aim to prospectively validate a new risk score model for primary prevention of SCD in ACHD patients, as well as the currently existing guideline recommendations. Patients are screened using a novel risk score to predict SCD as well as current ICD indications according to an international Consensus Statement. Patients are followed up for two years. The primary endpoint is the occurrence of SCD and sustained ventricular arrhythmias. The Study was registered at ClinicalTrials.gov (NCT03957824). Conclusion PREVENTION-ACHD is the first prospective study on SCD in ACHD patients. In the light of a growing and aging population of patients with more severe congenital heart defects, more robust clinical evidence on primary prevention of SCD is urgently needed. Electronic supplementary material The online version of this article (10.1007/s12471-019-1297-3) contains supplementary material, which is available to authorized users.

Objective Adult congenital heart disease (ACHD) patients are at risk of sudden cardiac death (SCD). However, methods for risk stratification are not yet well‐defined. The Tpeak‐Tend (TpTe) interval, a measure of dispersion of ventricular repolarization, is a risk factor for SCD in non‐ACHD patients. We aim to evaluate whether TpTe can be used in risk stratification for SCD in ACHD patients. Design From an international multicenter cohort of 25 790 ACHD patients, we identified all SCD cases. Cases were matched to controls by age, gender, congenital defect, and (surgical) intervention. Outcome Measures TpTe was measured on a standard 12‐lead ECG. The maximum TpTe of all ECG leads (TpTe‐max), mean (TpTe‐mean), and TpTe dispersion (maximum minus minimum) were obtained. Odds ratios (OR) for SCD cases vs controls were calculated using conditional logistic regression analysis. Results ECGs were available for 147 cases (median age at death 33.5 years (quartiles 26.2, 48.7), 66% male) and 267 controls. The mean TpTe‐max was 97 ± 24 ms in cases vs 84 ± 17 ms in controls (P

Background Swallowing function in individuals with Parkinson's disease (PD) can be negatively affected by dopaminergic medication with associated inhibition of brainstem reflexes. Three different “swallowing-safety” profiles of PD patients were previously observed, classified according to swallowing safety on and off levodopa. Methods Here, we investigated the effects of l-dopa on pulmonary function tests (PFTs) on 26 individuals with PD from the three different swallowing-safety profiles. PFTs results were compared to predicted values and direct comparisons between the groups with or without dysphagia were performed with nonparametric statistical tests (i.e., Kruskal–Wallis). Results A short (12-hour) withdrawal from l-dopa did not result in any significant changes in PFTs, and no differences on PFTs results were observed between the different dysphagic groups the on and off l-dopa state. No correlation was observed between the PFTs results with swallowing safety profiles of PD patients. Conclusions Although deglutition seems to be at least partially affected by dopaminergic repletion, dopaminergic mechanisms do not seem to be responsible for PD patients' performance in PFTs.

Background Successful activation mapping of ventricular tachycardia (VT) is dependent on the identification of a region of diastolic conduction by use of point-by-point sequential mapping. It is important to identify the site of transition from diastolic conduction to systolic activation of healthy myocardium (exit site) and differentiate this from nonvulnerable regions of the circuit. Objective We sought to determine the temporal and component characteristics of exit-site electrograms using simultaneous multielectrode endocardial mapping and to differentiate them from bystander sites during activation mapping. Methods Sixteen VTs induced in 12 patients with ischemic cardiomyopathy who underwent multielectrode mapping during VT performed with a custom-made 112-bipolar-electrode endocardial array were analyzed retrospectively. The activation sequence in systole and diastole was annotated, and the timing at exit and bystander sites of the near-field component was characterized in relation to surface electrocardiogram activation and to the far-field component. Spectral content of bipolar electrograms recorded at these sites was additionally analyzed to identify the near-field to far-field interval. Results The mean activation time at exit sites was 60.0 ± 31.5 ms (range 21–113 ms) ahead of surface QRS but was not significantly different from bystander sites (72.0 ± 55.0 ms, P = .63). However, the time delay from local to far-field activity was significantly lower at exit sites than at bystander sites (24.9 ± 15.6 vs 86.6 ± 92.0 ms, P = .003), which was confirmed by spectral analysis (10.0 ± 13.1 vs 89.0 ± 64.5 ms, P = .003). Conclusion Our analysis suggests that temporal-component analysis of diastolic electrograms during activation mapping of VT provides a practical method to differentiate nonvulnerable sites from the exit site without the need for pacing maneuvers.

Aims Sudden cardiac death (SCD) causes a large portion of all mortality in adult congenital heart disease (ACHD) patients. However, identification of high-risk patients remains challenging. Fragmented QRS-complexes (fQRS) are a marker for SCD in patients with acquired heart disease but data in ACHD patients are lacking. We therefore aim to evaluate the prognostic value of fQRS for SCD in ACHD patients. Methods and results From a multicentre cohort of 25 790 ACHD patients, we included tachyarrhythmic SCD cases (n = 147), and controls (n = 266) matched by age, gender, congenital defect and (surgical) intervention. fQRS was defined as ≥1 discontinuous deflection in narrow QRS-complexes, and ≥2 in wide QRS-complexes (>120 ms), in two contiguous ECG leads. We calculated odds ratios (OR) using univariable and multivariable conditional logistic regression models correcting for impaired systemic ventricular function, heart failure and QRS duration >120 ms. ECGs of 147 SCD cases (65% male, median age of death 34 years) and of 266 controls were assessed. fQRS was present in 51% of cases and 34% of controls (OR 2.0, P = 0.003). In multivariable analysis, fQRS was independently associated with SCD (OR 1.9, P = 0.01). The most common diagnose of SCD cases was tetralogy of Fallot (ToF, 34 cases). In ToF, fQRS was present in 71% of cases vs. 43% of controls (OR for SCD 2.8, P = 0.03). Conclusions fQRS was independently associated with SCD in ACHD patients in a cohort of SCD patients and matched controls. fQRS may therefore contribute to the decision when evaluating ACHD patients for primary prevention of SCD.

Specific congenital heart anomalies significantly increase the risk for late atrial arrhythmias, raising the question whether prophylactic arrhythmia operations should be incorporated into reparative open heart procedures. Currently no consensus exists regarding standard prophylactic arrhythmia procedures. Questions remain concerning the arrhythmia-specific lesions to perform, energy sources to use, need for atrial appendectomy, and choosing a right, left, or biatrial Maze procedure. These considerations are important because prophylactic arrhythmia procedures are performed without knowing if the patient will actually experience an arrhythmia. This review identifies congenital defects with a risk for the development of atrial arrhythmias and proposes standardizing lesion sets for prophylactic arrhythmia operations.

Background— Sudden cardiac death (SCD) is a major cause of mortality in adult congenital heart disease (ACHD) patients. SCD may be prevented by implantable cardioverter-defibrillator (ICD) implantation, but patient stratification remains troublesome. The 2014 Consensus Statement on Arrhythmias in ACHD patients and the 2015 European Society of Cardiology Guidelines specified recommendations for ICD implantation in ACHD patients for the first time. We assess the discriminative ability of these ICD recommendations for SCD in ACHD patients. Methods and Results— Of 25 790 ACHD patients in an international multicenter registry, we identified all SCD cases, matched to living controls by age, sex, congenital defect, and surgical repair. We assessed all primary prevention ICD recommendations listed in both documents. We used conditional logistic regression models to calculate odds ratios and receiver operating characteristic curves with area under the curve. Consensus Statement: One hundred twenty-four cases (median age at death, 33 years [26–44]; 67% men) and 230 controls were studied. In total, 41% of SCD cases and 17% of controls had an ICD recommendation (odds ratio, 5.9; P European Society of Cardiology Guidelines: Of one hundred fifty-seven cases (median age at death, 33 years [26–48]; 64% men) and 292 controls, 35% and 14% had an ICD recommendation, respectively (odds ratio, 4.8; P Conclusions— A minority of SCD cases had an ICD recommendation according to these guidelines, whereas the majority of SCD victims remained unrecognized. With an area under the curve of 0.6 to 0.7, the discriminative ability of both guidelines was mediocre. Critical clinical reasoning when deciding on ICD implantation in ACHD patients, therefore, remains vital.

The risk of ventricular arrhythmias in the adult congenital heart disease population increases with age. The mechanism, type, and frequency vary depending on the complexity of the defect, whether it has been repaired, and the type and timing of repair. Risk stratification for sudden death in patients with congenital heart disease is often challenging. Current recommendations provide a useful guide for management of these patients and risk stratification continues to evolve. Internal cardiac defibrillator implantation is often challenging due to limited transvenous access, often resulting in the need for epicardial or subcutaneous devices.

Society Guidelines PACES/HRS Expert Consensus Statement on the Recognition and Management of Arrhythmias in Adult Congenital Heart Disease Developed in Partnership Between the Pediatric and Congenital Electrophysiology Society (PACES) and the Heart Rhythm Society (HRS). Endorsed by the Governing Bodies of PACES, HRS, the American College of Cardiology (ACC), the American Heart Association (AHA), the European Heart Rhythm Association (EHRA), the Canadian Heart Rhythm Society (CHRS), and the International Society for Adult Congenital Heart Disease (ISACHD) Paul Khairy, MD, PhD, FRCPC (Chair),* George F. Van Hare, MD, FACC, FHRS (Co-Chair),y Seshadri Balaji, MBBS, PhD,y Charles I. Berul, MD, FHRS,y Frank Cecchin, MD, FACC,z Mitchell I. Cohen, MD, FACC, FHRS,y Curt J. Daniels, MD, FACC,** Barbara J. Deal, MD, FACC,y Joseph A. Dearani, MD, FACC,* Natasja de Groot, MD, PhD,{ Anne M. Dubin, MD, FHRS,y Louise Harris, MBChB, FHRS, Jan Janousek, MD, PhD,{ Ronald J. Kanter, MD, FHRS,y Peter P. Karpawich, MD, FACC, FAHA, FHRS,y James C. Perry, MD, FACC, FHRS,* Stephen P. Seslar, MD, PhD,y Maully J. Shah, MBBS, FHRS,y Michael J. Silka, MD, FACC, FAHA,x John K. Triedman, MD, FACC, FHRS,y Edward P. Walsh, MD, FACC, FHRS,y and Carole A. Warnes, MD, FRCP, FACC, FAHA** Pediatric and Congenital Electrophysiology Society (PACES) representative; yHeart Rhythm Society (HRS) representative; zAmerican College of Cardiology (ACC) representative; xAmerican Heart Association (AHA) representative; {European Heart Rhythm Association (EHRA) representative; Canadian Heart Rhythm Society (CHRS) representative; International Society for Adult Congenital Heart Disease (ISACHD) representative

Recognition and Management of Arrhythmias in Adult Congenital Heart Disease: Executive Summary Developed in partnership between the Pediatric and Congenital Electrophysiology Society (PACES) and the Heart Rhythm Society (HRS). Endorsed by the governing bodies of PACES, HRS, the American College of Cardiology (ACC), the American Heart Association (AHA), the European Heart Rhythm Association (EHRA), the Canadian Heart Rhythm Society (CHRS), and the International Society for Adult Congenital Heart Disease (ISACHD)

Aims Current conventional ablation strategies for ventricular tachycardia (VT) aim to interrupt reentrant circuits by creating ablation lesions. However, the critical components of reentrant VT circuits may be located at deep intramural sites. We hypothesized that bipolar ablations would create deeper lesions than unipolar ablation in human hearts. Methods and results Ablation was performed on nine explanted human hearts at the time of transplantation. Following explant, the hearts were perfused by using a Langendorff perfusion setup. For bipolar ablation, the endocardial catheter was connected to the generator as the active electrode and the epicardial catheter as the return electrode. Unipolar ablation was performed at 50 W with irrigation of 25 mL/min, with temperature limit of 50°C. Bipolar ablation was performed with the same settings. Subsequently, in a patient with an incessant septal VT, catheters were positioned on the septum from both the ventricles and radiofrequency was delivered with 40 W. In the explanted hearts, there were a total of nine unipolar ablations and four bipolar ablations. The lesion depth was greater with bipolar ablation, 14.8 vs. 6.1 mm ( P < 0.01), but the width was not different (9.8 vs. 7.8 mm). All bipolar lesions achieved transmurality in contrast to the unipolar ablations. In the patient with a septal focus, bipolar ablation resulted in termination of VT with no inducible VTs. Conclusion By using a bipolar ablation technique, we have demonstrated the creation of significantly deeper lesions without increasing the lesion width, compared with standard ablation. Further clinical trials are warranted to detail the risks of this technique.

Canadian electrophysiology (EP) fellowship programs have evolved in an ad hoc fashion over 30 years. This evolution has occurred in many fields in medicine and is natural when innovators and pioneers attract research fellows who help change the status quo from predominantly research to a predominantly clinical application and focus. Fellows not only push their supervisors and their centres into new areas of inquiry but also function at the most advanced level to encourage and teach junior trainees and to provide examples of excellence to residents, medical students, and other health professionals. Funding for fellows has never been provided in the traditional way through the Ministry of Health or the Ministry of Advanced Education. Each Canadian centre has over the years found novel ways to fund fellowship programs, and many centres have used value-adds from procurement programs. These sources of funding are eroding as provincial government agencies are beginning to assume procurement responsibilities and local flexibility to fund fellowships is lost. In particular, provincial government agencies feel that valuable financial resources should be restricted to Canadian trainees only, despite the international consensus that fellowship is an essential time for advanced trainees to travel abroad to acquire a broad a range of experience, learn new techniques and approaches, make lifelong research connections, and hopefully return home with these skills and expertise. This article summarizes the long history of EP fellowship training in Canada, as well as EP fellowship experiences at home and abroad by Canadian electrophysiologists, in an attempt to contextualize these new realities.